Advanced Micro Devices adjusted the prices on a number of its PC and server processors on Monday.

The chipmaker, in a regularly scheduled price adjustment, followed the introduction of higher-performance Opteron server chips with cuts of up to 35 percent on existing Opterons. AMD also lowered the prices of its Athlon 64 chips for desktop and notebook PCs by as much as 34 percent and cut its Sempron value chips by between 6 percent and 19 percent. But in a twist, it also slightly raised the prices on a handful of processors, including a pair of Athlon MP server chips and a Sempron for desktop PCs.

Most of AMD's Opteron price moves resulted in cuts of 18 percent or more. The chipmaker lowered prices on Opteron 800 processors, chips it designed to fit into servers with four or more processors, by up to 25 percent. The Opteron 848, for example, went down 25 percent from $1,165 to $873.

AMD enacted some of the biggest price changes in its Opteron 200 line for dual processor servers and workstations. It lopped between 19 percent and 34 percent off of those chips' prices, dropping the Opteron 244 and the Opteron 248 by 34 percent each. They are now $209 and $455, respectively.

The Opteron 150, part of the Opteron line for single processor servers and workstations, saw the biggest drop. It was lowered by 35 percent to $417.

AMD kept the price of its flagship desktop processor, the Athlon 64 FX-55, the same at $827. But it slashed prices by up to 34 percent on many of the rest of its desktop Athlon 64s.

The company nipped the price of its flagship Athlon 64 4000+ chip by 12 percent to $643. The Athlon 64 3800+ and 3700+ processors were lowered by 34 percent and 30 percent, respectively, to $424 and $329.

AMD clipped a number of Mobile Athlon 64 chips' prices as well. The Mobile Athlon 64 3700+ for large, desktop replacement notebooks, fell by 30 percent to $321, in one example.

AMD also dropped the prices of its Sempron processor for low-price desktops and notebooks.

The Sempron for desktops using Socket A motherboards--the same type of socket used by the company's older Athlon XP chip--were among those cut. The Sempron 2800+ for Socket A boards was clipped by 17 percent to $90. The Mobile Sempron 2800+ for full-size notebooks, meanwhile, dropped 19 percent to $87.

Although AMD normally reduces the price of a given chip as it gets older, the company occasionally increases the price on a chip. This time around, it stepped up prices on two Athlon MP chips and one Sempron. The Athlon MP 2800+ was upped $27, to $201, while the Athlon MP 2600+ was increased $20, to $151. AMD also bumped up its desktop Sempron 2400+ by $7, to $68.

AMD's list prices reflect two different ways in which it sells its chips. The prices it lists for notebook and server chips represent prices for chips sold in 1,000-unit lots to PC makers. However, its desktop PC processor prices reflect chips that are sold in kits with heat sinks and fans. These processor-in-box prices, which also include a three-year warranty, reflect what system builders who purchase chips via an authorized AMD distributor would pay when purchasing the kits in 1,000-unit lots, AMD has said. Street prices for individual chips tend to vary and are often higher than AMD's list prices.